Method of administering hyaluronan formulation for the amelioration of osteoarthritis

ABSTRACT

Disclosed is a method for mitigating or ameliorating osteoarthritis in vertebrate subjects including administering to a subject a therapeutically effective amount of an exogenous hyaluronan formulation. Also disclosed is an oral or parenteral hyaluronan composition comprising a polydisperse hyaluronan and a pharmaceutically acceptable carrier, and a method of manufacturing the composition.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. application Ser. No.11/595,657, filed Nov. 10, 2006, which claims the benefit of the filingdate under 35 U.S.C. §119(e) of United States Provisional Applicationfor Patent Ser. No. 60/735,551 filed on Nov. 10, 2005, and thisapplication is also a continuation-in-part of United States Applicationfor patent Ser. No. 12/165,278, filed Jun. 30, 2008, which claims thebenefit of the filing date under 35 U.S.C. §119(e) of U.S. ProvisionalApplication for Patent Ser. No. 60/937,909 filed on Jun. 30, 2007, allof which are hereby incorporated by reference.

TECHNICAL FIELD

The present disclosure relates to a method of administering acomposition comprising a therapeutically effective amount of anexogenous hyaluronan formulation to a subject for preventing, slowing,attenuating, mitigating, and/or ameliorating the loss of articularcartilage in osteoarthritis.

BACKGROUND

Osteoarthritis is characterized by the progressive loss of articularcartilage. Eventually, in many cases, the entirety of the articularcartilage in certain diarthrodial joints such as the knee, where thefemur and tibia articulate, is lost.

Joint injury and osteoarthritis are major causes of lameness anddisability. Mammals have pain that typically worsens with weight-bearingand activity and improves with rest. Inflammation may be mild andlocalized in the affected joint. Although the etiology of osteoarthritisremains unknown, biomechanical stresses and biochemical changes in thearticular cartilage, subchondral bone and synovial membrane, as well asgenetic factors, are all important in its pathogenesis. The synovialfluid's capacity to lubricate and to absorb impact is reduced inaffected joints. These changes are clue to a reduction in the size,concentration and quality of hyaluronan molecules naturally present insynovial fluid.

Commonly used treatments and medications only provide palliative care.Palliative care is defined as any form of medical care or treatment thatconcentrates on reducing the severity of disease symptoms, rather thanhalting or delaying progression of the disease or providing a cure.Non-Steroidal Anti-inflammatory Drugs (NSAIDs) are frequently prescribedor self-administered ad libitum. Types include aspirin, ibuprophen,acetaminophen, and naproxen. Although NSAIDs work well for theirintended purpose, long-term use of these drugs can cause stomachproblems such as ulcers and bleeding.

In April 2005, the FDA asked manufacturers of NSAIDs to include awarning label on their product to alert users of an increased risk forcardiovascular events (heart attacks and strokes) and gastrointestinalbleeding. Certain NSAIDs may also weaken bone and increase the risk ofbone fractures.

COX-2 inhibitors (coxibs) are also used to treat symptoms. Coxibs blockan inflammation-promoting enzyme called COX-2. This class of drugs wasinitially believed to work as well as traditional NSAIDs, but with fewerstomach problems. However, numerous reports of heart attacks and strokeshave prompted the FDA to re-evaluate the risks and benefits of theCOX-2s. Certain COX-2s have been withdrawn from the US market followingreports of heart attacks in some patients taking the drugs. COX-2s stillcommercially available are labeled with strong warnings and arecommendation that it be prescribed at the lowest possible dose for theshortest duration possible. However, neither NSAIDs nor COX-2 inhibitorsare known to stop or restore the loss of articular cartilage, which isthe hallmark of osteoarthritis and the cause of the symptoms.

Steroids and artificial joint fluid (Synvise, Hyalgan, etc.) can beinjected directly into the joint capsule to reduce pain and inflammationfor up to six months but have attendant injection site risks and do notimprove the underlying cartilage condition.

Natural substances marketed in the United States as dietary supplementsare also administered in cases of osteoarthritis. In particular,glucosamine, chondroitin sulfate, and methylsulfonylmethane (MSM) areadministered in order to provide some relief from the symptoms ofosteoarthritis. However, none of these substances is known to addresscartilage loss, the root cause of osteoarthritis symptoms.

While exogenous hyaluronan has been administered via intraarticular andintravenous injections to mammals, it is not generally known thathyaluronan in an effective amount could be absorbed following perioraladministration. Furthermore, there is no teaching in the art of a methodfor preventing, slowing, attenuating, mitigating, and/or amelioratingthe loss of articular cartilage in osteoarthritis in a vertebratesubject, the method comprising the step of administering a compositioncomprising a therapeutically effective amount of an exogenous hyaluronanto the subject. The present disclosure provides such a method.

SUMMARY

Disclosed is a method for preventing, slowing, attenuating, mitigating,and/or ameliorating the loss of articular cartilage in osteoarthritis ina vertebrate subject, the method comprising administering a compositioncomprising a therapeutically effective amount of an exogenous hyaluronanformulation to a vertebrate subject.

Also disclosed is a composition comprising a polydisperse hyaluronanformulation and a pharmaceutically acceptable carrier.

BRIEF DESCRIPTION OF THE DRAWINGS

The patent or application file contains at least one drawing executed incolor. Copies of this patent or patent application publication withcolor drawing(s) will be provided by the Office upon request and paymentof the necessary fee.

FIG. 1 is a photograph of the histopathology tissue section of a ControlMouse knee (Group A untreated Control Mouse six week post surgery;average score 5.33/24).

FIG. 2 is a photograph of the histopathology tissue section of a ControlMouse knee (Group 13 Saline 3 week Control average score 10.7/24).

FIG. 3 is a photograph of the histopathology tissue section of a ControlMouse knee (Group C Saline 6 week Control average score 12.8/24).

FIG. 4 is a photograph of the histopathology tissue section of aTreatment Mouse knee (Group 1) MBH3™ week Treated average score 7.2/24).

FIG. 5 is a photograph of the histopathology tissue section of aTreatment Mouse knee (Group MBH3™ 6 week Treated average score 7.8/24).

DETAILED DESCRIPTION

Disclosed is a method of administering a modified hyaluronan biopolymerformulation to a vertebrate subject for the purposes of preventing,slowing, attenuating, mitigating, and/or ameliorating the loss of lossof articular cartilage in osteoarthritis. By mitigating or amelioratingthe loss of articular cartilage in the subject, the method also treatsjoint discomfort that is associated with osteoarthritis. The methodcomprises administering a composition comprising a therapeuticallyeffective amount of exogenous hyaluronan biopolymer to the subject.

The method of administering a therapeutically effective amount of thehyaluronan biopolymer to a subject may be accomplished by oral orparenteral administration. With respect to oral administration, thehyaluronan formulation may be administered directly into the subject'smouth. Alternatively, oral administration may be achieved by includingthe therapeutically effective amount of the hyaluronan formulation inthe subject's food or water. For example, the hyaluronan formulation maybe provided in the form of a syrup that is useful for adding to foodrations. According to certain illustrative embodiments, parenteraladministration of the therapeutically effective amount of the hyaluronanmay comprise subcutaneous administration, intramuscular administration,and intravenous administration.

A therapeutically effective amount of hyaluronan biopolymer per kg bodyweight of the test subject can be determined by one having ordinaryskill in the art without having to resort to undue experimentation.According to certain illustrative embodiments, and without limitation,therapeutically effective amounts may comprise from about 0.2 to about 5mg per kg body weight of the subject, from about 0.4 to about 4 mg perkg body weight of the subject, from about 0.6 to about 3 mg per kg bodyweight of the subject, from about 0.8 to about 2 mg per kg body weightof the subject, and about 1 mg per kg body weight of the subject.

The term “hyaluronan” as used herein refers to any physiological saltform of hyaluronic acid. The hyaluronan biopolymer is polydisperse andtherefore comprises a blend or mixture of hyaluronan polymers havingdifferent molecular masses. Without limitation, hyaluronan biopolymersthat are administered to the vertebrate subject may comprise a blend ofpolymers having molecular weights in range from about 50,000 to about8,000,000 Daltons. By way of illustration, suitable hyaluronan polymersmay comprise molecular weights from about 500,000 to about 2,500,000Daltons, from about 750,000 to about 2,250,000 Daltons, from about1,000,000 to about 2,000,000 Daltons, from about 1,250.000 to about1,750,000 Daltons, or from about 1,375,000 to about 1,625,000 Daltons.According to certain embodiments, the biopolymers comprise an averagemolecular weight of about 1,500,000 Daltons.

The hyaluronan formulation thus comprises hyaluronan molecules ofappropriate size(s). For optimal absorption by a warm-blooded mammal,the hyaluronan molecule must be shortened in length. Long chains ofhyaluronan molecules tend to break down in an acidic environment,because the acid cleaves at and breaks some of the glycosidic bondswithin the hyaluronan molecule. Accordingly, degradation of long-chainhyaluronan polymers by acid can yield readily absorbed hyaluronanpolymers. It has been found that citric acid or ascorbic acid are usefuland effective in lowering the pH and in cleaving longer-chain hyaluronanpolymers into somewhat shorter hyaluronan polymers which are morereadily absorbed along a mammal's gastrointestinal tract.

According to illustrative embodiments, the biopolymer compositioncomprises a product of microbial fermentation. By producing the polymerby extra-cellular microbial fermentation, it is considered to be a veganproduct. Accordingly, the hyaluronan may contain no animal derivedmaterials, which minimizes the risk of transmission of animal spongiformencephalopathy. Producing the hyaluronan polymer by microbialfermentation also results in more consistent molecular profile,molecular weight and narrow polydispersity that is optimized for oralbioavailability. According to certain embodiments, the formulation maybe made, for example, from sodium hyaluronate that is bacteriallysynthesized.

The hyaluronan composition comprises a pharmaceutically acceptablecarrier that is safe for human or veterinary consumption. Withoutlimitation, and by way of example only, a suitable carrier for thehyaluronan composition is water.

According to certain embodiments, the hyaluronan formulation may containat least one non-water excipient pharmaceutically acceptable. Withoutlimitation, and by way of example only, a suitable excipient for thehyaluronan composition comprises sodium chloride. Any of many excipientsdescribed in the current edition of the Handbook of PharmaceuticalExcipients (5th edition, RC Rowe et al, eds.) may be suitable forinclusion in a formulation according to the invention. A non-limitingexample of such an excipient is xanthan gum.

The hyaluronan composition may also include a pH altering agent. The pHaltering agent included hyaluronan composition may comprise an inorganicor organic acid. Without limitation, and by way of example only, asuitable pH altering agent for the hyaluronan composition comprises apharmaceutically acceptable organic acid, such as citric acid orascorbic acid. According to certain embodiments, and without limitation,citric acid or ascorbic acid may be included in the hyaluronancomposition in an amount effective to provide a pH of the hyaluronancomposition that is between about 2.5 and about 4.5.

During the manufacture of the hyaluronan formulation, the inclusion ofthe pH altering agent provides a hyaluronan formulation lowers the pHand maintains the pH in the range of about 2.5 to about 4.5 for adesired period of time. The limited period of time may be less thanabout sixteen hours. The limited period of time may be less than abouteight hours. The limited period of time may be less than about fourhours. The limited period of time may be less than about two hours. Thelimited period of time may be less than about one hour. A person skilledin the art will recognize various means of thus lowering the pH. Theintrinsic viscosity and the specific gravity of the formulation are alsoimportant parameters for manufacturing optimization.

According to certain illustrative embodiments, the composition comprisesa therapeutically effective amount of hyaluronan and an antimicrobialpreservative or stabilizer. Any known antimicrobial preservative that isgenerally regarded as safe for human or veterinary consumption may beincluded in the hyaluronan composition. Without limitation, according tocertain embodiments, suitable antimicrobial preservatives includepotassium sorbite, sodium benzoate and mixtures thereof. Theantimicrobial preservative(s) may be present in an amount of from about0.1 mg/mL to about 5 mg/mL. Inclusion of such a preservative imparts ashelf-life to a formulation of as much as six months.

The biopolymer composition and method of administration may be usefulfor treating afflictions of cartilage of a wide variety of vertebratespecies. For example, and by way of example only, the hyaluronancomposition may be administered to any of rat, murine, human, equine,canine or feline species.

The hyaluronan composition and method of administration to thevertebrate subject is useful in treating osteoarthritis. The compositionor method is useful in treating the osteoarthritis condition that is aresult of either an injury or a degenerative process other than injury.

The hyaluronan may be formulated into a wide variety of orallyingestible compositions. Hyaluronan is a non-sulfated glycosaminoglycanwhich can be dispensed in aqueous oral formulations. The hyaluronan maybe formulated with an acceptable carrier to provide an orally ingestibleliquid or a solid or semi-solid food product. Liquid forms includesolutions, suspensions, emulsions, gels, syrups, and the like. Accordingto certain illustrative embodiments, the hyaluronan composition may beformulated with an orally ingestible liquid carrier to provide an orallyingestible hyaluronan composition. For example, the hyaluronan may beformulated with an orally ingestible liquid carrier to provide abeverage, dietary supplement formulation, or nutritional supplemental.The beverages, dietary supplements and nutritional supplements may beprovided ready for oral ingestion or may be provided in a concentratefor that requires dilution with acceptable liquids prior to oralingestion. According to alternative embodiments, the hyaluronan may beformulated into other orally ingestible product forms, such as powders,pills, lozenges, tablets, caplets, capsules, gel capsules and the like.Flavoring agents may also be added to the hyaluronan compositions toprovide a more palatable orally ingestible composition.

The orally administrable hyaluronan composition may further includenutritionally effective amounts of an additional supplement. Accordingto certain embodiments, the hyaluronan composition further comprisesnutritionally effective amounts of at least one vitamin, or at least onemineral or a combination of at least one vitamin and at least onemineral. According to certain embodiments, the hyaluronan compositioncomprises a therapeutically effective amount of hyaluronan and anutritionally effective amount of at least one vitamin. According tocertain embodiments, the hyaluronan composition comprises atherapeutically effective amount of hyaluronan and a nutritionallyeffective amount of more than one different vitamin. According tocertain embodiments, the hyaluronan composition comprises atherapeutically effective amount of hyaluronan and a nutritionallyeffective amount of at least one mineral. According to certainembodiments, the hyaluronan composition comprises a therapeuticallyeffective amount of hyaluronan and a nutritionally effective amount ofmore than one different mineral. According to certain embodiments, thehyaluronan composition comprises a therapeutically effective amount ofhyaluronan and a nutritionally effective amount of at least one vitaminand at least one mineral. According to certain embodiments, thehyaluronan composition comprises a therapeutically effective amount ofhyaluronan and a nutritionally effective amount of more than onedifferent vitamin and at least one mineral. According to certainembodiments, the hyaluronan composition comprises a therapeuticallyeffective amount of hyaluronan and a nutritionally effective amount ofat least one vitamin and more than one different mineral. According tocertain embodiments, the hyaluronan composition comprises atherapeutically effective amount of hyaluronan and a nutritionallyeffective amount of more than one different vitamin and more than onedifferent mineral.

The pharmacokinetics of the hyaluronan formulation are noteworthy.Scintigraphy of a dog to which has been administered a single oraladministration of a technetium 99m-labeled formulation demonstratesabsorption and distribution to organs, joints and bones within two hourspost-administration. Scintigraphy of a rat to which has beenadministered a single oral administration of a technetium 99m-labeledformulation demonstrates absorption and distribution to organs, jointsand bones within four hours post-administration. Accordingly, thepresent hyaluronan formulation is effectively delivered to joints aftera single oral administration. Traces of a formulation according to theinvention were observed in as little as 30 minutes post-administrationfollowing a single oral administration.

The present hyaluronan formulation by preventing, slowing, attenuating,mitigating, and/or ameliorating the loss of articular cartilage conferschondroprotection to a mammal to which the formulation is administeredif the mammal is in need of chondroprotection. A formulation accordingto the invention confers disease modification to a mammal to which theformulation is administered if the mammal is in need of diseasemodification. By providing disease modification, the administration ofthe formulation enhances chondrocyte hyaluronan and proteoglycansyntheses, thereby reducing the production and activity ofproinflammatory mediators and matrix metalloproteinases. This issignificant for reducing nerve impulses and nerve sensitivity associatedwith the pain of osteoarthritis. Preventing, slowing, attenuating,mitigating, and/or ameliorating the loss of articular cartilage alsoresults in a lessening of inflammation, and a reduction in pain, in amammal to which the formulation is administered.

The formulation also imparts salutary regulatory effects ongranulocytes, monocytes, fibroblasts, and endothelial cells, as well ason the healing of wounds and various joint disorders. Animal-basedstudies have demonstrated positive effects of the formulation on pain inthe joint and on heat shock proteins, which are significant inosteoarthritis. In addition to the stimulating effect onhyaluronan-producing synoviocytes, the anti-inflammatory and analgesicproperties according to the invention provide symptomatic relief fromthe pain associated with osteoarthritis. The formulation protects humancartilage in explant culture and was shown to facilitate restoration ofproteoglycan in damaged cartilage.

The hyaluronan composition may also include a drug component alone or inaddition to the nutritional supplemental.

Additionally provided is a method for manufacturing a hyaluronanformulation, said formulation being useful for the purposes ofpreventing, slowing, attenuating, mitigating, and/or ameliorating theloss of loss of articular cartilage in osteoarthritis. The methodcomprises the step of maintaining the pH of an aqueous solutioncontaining hyaluronan to a pH of from about 2.5 to about 4.5.

EXAMPLES

The following examples are provided to further illustrate the hyaluronancomposition and method of administering the exogenous hyaluronan tovertebrate subjects. It should be noted that the examples are providedfor illustration and should not be construed to limit the scope of thecomposition or method of administering the composition in any manner.

Effects of MBH3™ (Hyaluronan Biopolymer) On Cartilage Loss in a MouseModel of Monoarthritis

Osteoarthritis (OA) is characterized by progressive articular cartilageloss. A study was designed and conducted using an establishedhistopathological scoring system to evaluate specifically the effects ofan orally administered, polydisperse hyaluronan biopolymer (MBH3™,Cogent Solutions Group LLC) in a mouse model of monoarthritis.

Thirty 10 week old male C57BL/6 mice purchased from Charles RiverLaboratories were subjected to a meniscotibial ligament transactionsurgery of the left knee. This surgery creates a slowly advancinginstability condition that mimics the loss of articular cartilage inhumans with OA. After six weeks mice were randomly assigned to 5 groups.Group A (Untreated Controls N=6) was cuthanized, their kneesdecalcified, paraffin embedded, stained with Saffrin-O and scored(Pritzker et al.) to confirm disease onset and cartilage loss. Ahistopathological score of 1 indicates articular cartilage which isintact and pristine. A score of less than 10 indicates that a great dealof healthy articular cartilage remains. A histopathological score of 24indicates total loss of articular cartilage as is observed in verysevere cases. Following confirmation of cartilage loss at week 6 postsurgery Group 13 (Controls. N=6) was gavaged 5 days/week for 3 weekswith saline; Group C (Controls, N6) was gavaged 5 days/week for 6 weekswith saline; Group D (Treated, N=6) was gavaged 5 days/week for 3 weekswith MBH3™ at a dose of 10 mg/kg; and Group E (Treated, N=6) was gavaged5 days/week for 6 weeks with MBH3™ at a dose of 10 mg/kg. At the end ofthree weeks of treatment Groups B and D were euthanized, scored andcompared. At the end of the six weeks treatment Groups C and E wereeuthanized, scored, and compared.

The average score of Group A (6 week surgery) was 5.33/24, indicatingthe onset of osteoarthritis disease and serving as a baseline. Theaverage score in Group B (3 week saline control) was 10.7/24 versus theaverage score of Group D (3 week MBH3™ treated) was 7.2/24: the averagescore in Group C (6 week saline control) was 12.8/24 versus the averagescore of Group E was 7.8/24. The result of this study strongly supportsthe disease modifying and protective benefits of MBH3™ when used in anestablished model of osteoarthritis. To our knowledge this is the firsttime that an orally administered, exogenous hyaluronan biopolymer hasbeen shown to have such benefits.

Likewise, through parenteral administration of a buffered hyaluronansolution, such as through subcutaneous or intramuscular administration,similar effects are observed. It will be apparent to those skilled inthe art to which the present invention pertains how to make and how touse such a buffered hyaluronan solution for parenteral administration.

While the method for administering hyaluronan to vertebrate subject hasbeen described above in connection with certain illustrativeembodiments, it is to be understood that other embodiments may be usedor modifications and additions may be made to the described embodimentsfor performing the same function without deviating therefrom.Furthermore, all embodiments disclosed are not necessarily in thealternative, as various embodiments may be combined to provide thedesired characteristics. Variations can be made by one having ordinaryskill in the art without departing from the spirit and scope of thedisclosed method. Therefore, the method should not be limited to anysingle embodiment, but rather construed in breadth and scope inaccordance with the recitation of the attached claims. Equivalents willbe readily apparent to those skilled in the art.

I claim:
 1. A method for slowing, attenuating, mitigating, and/orameliorating the loss of articular cartilage in a vertebrate subject,the method comprising the step of orally administering a liquidcomposition comprising a therapeutically effective amount of exogenoussynthesized polydisperse hyaluronan composition comprising a blend ofhyaluronan polymers having different molecular masses from about1,250,000 to about 2,500,000 Daltons and a pharmaceutically acceptablecarrier to the subject.
 2. The method of claim 1, wherein thecomposition comprises from about 0.2 to about 5 mg hyaluronan per kgbody weight of the subject.
 3. The method of claim 2, wherein thecomposition comprises from about 0.4 to about 4 mg hyaluronan per kgbody weight of the subject.
 4. The method of claim 3, wherein thecomposition comprises from about 0.6 to about 3 mg hyaluronan per kgbody weight of the subject.
 5. The method of claim 4, wherein thecomposition comprises from about 0.8 to about 2 mg hyaluronan per kgbody weight of the subject.
 6. The method of claim 5, wherein thecomposition comprises about 1 mg hyaluronan per kg body weight of thesubject.
 7. The method of claim 1, wherein the composition furthercomprises at least one pharmaceutically acceptable excipient.
 8. Themethod of claim 7, wherein the carrier comprises water.
 9. The method ofclaim 8, wherein the composition comprises sodium chloride.
 10. Themethod of claim 8, wherein the composition comprises citric acid. 11.The method of claim 7, wherein the composition comprises anantimicrobial preservative.
 12. The method of claim 11, wherein thepreservative is at least one of potassium sorbate and sodium benzoate.13. The method of claim 1, wherein the hyaluronan comprises molecularweights from about 1,250,000 to about 1,750,000 Daltons.
 14. The methodof claim 13, wherein the hyaluronan comprises molecular weights fromabout 1,375,000 to about 1,625,000 Daltons.
 15. The method of claim 14,wherein the hyaluronan is of median molecular weight about 1,500,000Daltons.
 16. The method of claim 1, wherein the hyaluronan is a productof microbial fermentation.
 17. The method of claim 1, wherein thesubject is a human subject.
 18. The method of claim 1, wherein thesubject is an equine subject.
 19. The method of claim 1, wherein thesubject is a canine subject.
 20. The method of claim 1, wherein thesubject is a feline subject.
 21. The method of claim 1, wherein the lossof articular cartilage is a result of injury.
 22. The method of claim 1,wherein the loss of articular cartilage is a result of a process otherthan injury.
 23. The method of claim 1, wherein the pH of thecomposition is between about 2.5 and about 4.5.